From 4844225eedd6c9638cf529be14c8c924eabed13a Mon Sep 17 00:00:00 2001
From: rh389 <roberthogan@blueyonder.co.uk>
Date: Wed, 11 Jan 2017 22:28:07 -0800
Subject: [PATCH] JavaScriptLoader BCBundle version check

Summary:
Currently a build warning is thrown by `if (header.BCVersion != runtimeBCVersion) ...` because `runtimeBCVersion` is signed, apparently because `-1` is used to mean that the runtime has no support for bytecode bundles.

This PR splits out the error case of the runtime not supporting BC bundles from the case of a version mismatch.

Tested as much as I could by building and running `UIExplorer` - I haven't attempted to use real bytecode bundles.
Closes https://github.com/facebook/react-native/pull/11806

Differential Revision: D4408608

fbshipit-source-id: a1d868bb2064588e6a20827692629a46b6ba1e74
---
 React/Base/RCTJavaScriptLoader.h  |  1 +
 React/Base/RCTJavaScriptLoader.mm | 13 +++++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/React/Base/RCTJavaScriptLoader.h b/React/Base/RCTJavaScriptLoader.h
index 1d32372cd56..c1d30ce2016 100755
--- a/React/Base/RCTJavaScriptLoader.h
+++ b/React/Base/RCTJavaScriptLoader.h
@@ -20,6 +20,7 @@ NS_ENUM(NSInteger) {
   RCTJavaScriptLoaderErrorFailedStatingFile = 3,
   RCTJavaScriptLoaderErrorURLLoadFailed = 3,
   RCTJavaScriptLoaderErrorBCVersion = 4,
+  RCTJavaScriptLoaderErrorBCNotSupported = 4,
 
   RCTJavaScriptLoaderErrorCannotBeLoadedSynchronously = 1000,
 };
diff --git a/React/Base/RCTJavaScriptLoader.mm b/React/Base/RCTJavaScriptLoader.mm
index 1d0f3cdec88..eacdf024f22 100755
--- a/React/Base/RCTJavaScriptLoader.mm
+++ b/React/Base/RCTJavaScriptLoader.mm
@@ -142,10 +142,19 @@ RCT_NOT_IMPLEMENTED(- (instancetype)init)
     return nil;
 
   case facebook::react::ScriptTag::BCBundle:
-    if (header.BCVersion != runtimeBCVersion) {
+    if (runtimeBCVersion == JSNoBytecodeFileFormatVersion || runtimeBCVersion < 0) {
+      if (error) {
+        *error = [NSError errorWithDomain:RCTJavaScriptLoaderErrorDomain
+                                     code:RCTJavaScriptLoaderErrorBCNotSupported
+                                 userInfo:@{NSLocalizedDescriptionKey:
+                                              @"Bytecode bundles are not supported by this runtime."}];
+      }
+      return nil;
+    }
+    else if ((uint32_t)runtimeBCVersion != header.BCVersion) {
       if (error) {
         NSString *errDesc =
-          [NSString stringWithFormat:@"BC Version Mismatch. Expect: %d, Actual: %d",
+          [NSString stringWithFormat:@"BC Version Mismatch. Expect: %d, Actual: %u",
                     runtimeBCVersion, header.BCVersion];
 
         *error = [NSError errorWithDomain:RCTJavaScriptLoaderErrorDomain